• 2021-04-14
    设[0,1,0,1,1]为来自两点分布总体的样本观测值,的矩估计值为( )。https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/4cbd471272cc498ab6295c9cde85bea2.png
  • 3/5
    本题目来自[网课答案]本页地址:https://www.wkda.cn/ask/pmmtjatezppexo.html

    内容

    • 0

      设是正态总体的总体容量为2的样本,为未知参数,则的无偏估计是( )。https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/bc800973e9f644959dab1f715bb9d2db.png

    • 1

      [0,2,2,3,3]为来自均匀分布总体的样本观测值,则的矩估计值为()。 A: 4 B: 1            C: 3                 D: 2

    • 2

      通过点<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/a13927df1bf542dfa036a32b10364f69.png" />的拉格朗日插值基函数<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/65695a42c7a14b649b6aa4fb68f7e499.png" />满足( ) A: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/99af333f3e934ef6a75022ee1e728b53.png" />=1,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/7769611ac5cd4c93975be7c41a49ae71.png" /> B: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/99af333f3e934ef6a75022ee1e728b53.png" />=1,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/7769611ac5cd4c93975be7c41a49ae71.png" /> C: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/99af333f3e934ef6a75022ee1e728b53.png" />=0,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/7769611ac5cd4c93975be7c41a49ae71.png" /> D: <img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/99af333f3e934ef6a75022ee1e728b53.png" />=0,<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/202009/f80e8e400f3f4916bcaf6b5fde757f16.png" />

    • 3

      为使锅垢中难溶于酸的CaSO4转化为易溶于酸的CaCO3,常用Na2CO3处理,反应式为CaSO4+CO32-<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/88320eab77594b6abf0039ab0efe3c57.png" />CaCO3+SO42-,此反应的标准平衡常数为()。 A: K<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/e8c371ce6b96487e829331bb8dee134f.png" />(CaSO4)·K<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/e8c371ce6b96487e829331bb8dee134f.png" />(CaCO3) B: K<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/e8c371ce6b96487e829331bb8dee134f.png" />(CaCO3)/K<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/e8c371ce6b96487e829331bb8dee134f.png" />(CaSO4) C: [K<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/e8c371ce6b96487e829331bb8dee134f.png" />(CaSO4)·K<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/e8c371ce6b96487e829331bb8dee134f.png" />(CaCO3)]1/2 D: K<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/e8c371ce6b96487e829331bb8dee134f.png" />(CaSO4)/K<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/e8c371ce6b96487e829331bb8dee134f.png" />(CaCO3)

    • 4

      下图电路ab端的等效电阻为____Ω()<img src="https://image.zhihuishu.com/zhs/doctrans/docx2html/201911/467e7c93e1bf491582e0a57566fa878e.png" > A: 1.2 B: 1 C: 2 D: 0.4